Pneumatic cushion for vehicles



L. a. Gauss. PNEUMATIC CUSHION FOR VEHICLES. APPLICATION FILED 0(ZT.1B.1915. 1,331,564.

RENEWED APR. 22, 1918.

atented Feb. 24, 1920.

WITNESSES:

UNITED STATES PATENT oFrIoE LUCIEN R. GRUSS, OF SAN FRANCISCO,CALIFORNIA, ASSIGNOIR- T0 PNEUMATIC CUSHION COMPANY, OF SAN FRANCISCO,CALIFORNIA, A-CORPORATION OF ARIZONA.

PNEUMATIC CUSHION FOR VEHICLES.

Specification of Letters Patent.

Patented Feb. 24, 1920.

Application filed. October 18, 1915, Serial No. 56,392. Renewed April22, 1918. Serial No. 230,170.

To all wiiom it may concern:

Be it known that I, LUCIEN R. Gauss, a citizen of the United States,residing at the city and county of San Francisco and State ofCalifornia, have invented new and useful Improvements in PneumaticCushions for Vehicles, of which the following is a specification.

This invention relates to a pneumatic cushion for vehicles, and pertainsparticularly to devices of the character shown in my prior patent,1,142,162, entitled Fluidpressure cushioning and weighing mechanismdated June 8, 1915. L

The object of the present invention is to provide first, an improvedform of piston construction and connection; second, a novel form ofcylinder construction which permits the formation of an oil seal betweenthe telescoping cylinders; and third, to provide means which willprevent accumulation or formation of air pockets in the oil chamber,these improvements being the result ofexperience and of actual operationof the invention.

The invention consists of the parts and the construction and combinationof parts, as hereinafter more fully described and claimed, havingreference to the accompanyiug drawings, in which Figure l is a centralvertical section through the device, showing the pistons, and parts ofthe interior tube or cylinders in side elevation.

Fig, 2 is a central vertical section' on line 2-2,-Fig. 3.

Referring to the drawingsin detail A indicates a cylinder, the upper endof which is closed by means of a head 2 to form a cushion or compressionchamber 3. Concentrically positioned within and spaced from cylinder Ais a cylinder or barrel This is secured to the head 2 as at 5 andcarries a piston 6 on its lower end. Slld. ably mounted telescope-wiseexterior of the barrel 4 and within cylinder A is a cylinder 7, andslidably mounted within the barrel is a piston 8, whichgis connected tocylinder 7 by means of a piston rod 9 and p a. socket joint 10, so thatthe two'may move central opening 13 formed in the piston 6,

which opening also permits a free movement of the piston rod 9therethrough. By referring to Fig. 2 it will be seen that compartment 11is of smaller interior diameter than compartment 12. This is ofconsiderable importance, as will hereinafter be described.

For the purpose of maintaining a seal between the inner barrel 4, theintermediate cylinder 7 and the main cylinder A a groove 14 has been cutin the upper end and inner side of the cylinder 7. The exterior face ofcylinder 4 has also been cut on a taper so as to form a gradual decreasein the exterior diameter, said decrease producing the smallest diameterat the lower end, as indicated at 15, and the largest diameter at theupper en l, as indicated at 16. This taper construction produces a loosefit between the inner barrel and intermediate barrel, thus permittingplay between same, and also permitting the formation of an oil filmbetween same, said oil being admitted by providing an oil cup 17 ofsuitable construction which introduces oil into the annular space 18,where it flows down and collects in the pocket 14- formed in the upperend of the cylinder 7. An oil seal is thus formed at this point whichnot only lubricates the contacting faces but also forms .aseal toprevent the admission or escape of air between the contacting faces ofthe cylinders.

Another feature of the present invention is'the piston construction asshown. Each piston 6 and 8 is provided with a cupleather 19, which isautomatically expanded by means of an annular follower-head 20 anda coilspring 21, which areintroduced between the heads of the pistons and theinterior of the cup-leather proper. These coii springs exert suiiicientpressure on the follower-heads to force these down within thecup-leather, thus not only forcing the c'upleather into contact with thecylinder walls but they also automatically serve to take up wear betweenthe contacting parts. The.

lower end of piston 8 is provided with a concave bottom, as indicated at22, and the upper end of the piston rod is hollowed out as at 23 to forma fluid-passage between compartment 11 and compression. chamber 3, saidfluid passage being opened or closed by means of a check valve 24 at theupper end, and being in communication with compartment 11 through meansof a plurality of radially spaced passages 25 formed at thelower end.These passages are so disposed as to communicate with the pocket formedby the concave end of the piston and will in this manner liberate anyair which might otherwise have a tendency to accumu late atthis point.Air passages such. as indicated at 26 have also been formed in thecup-leather groove of the lower piston 6 to permit the escape of airwhich might otherwiseaccumu'late in the groove.

In practice chambers 11 and 12 are charged with a liquid suchasoil,vwhich also stands normally in the compression I chamber 3, aninch OI'tWO above the piston, above whlch level the device is chargedwith air. at a desired pressure through an ordinary form of bicyclevalve 28, which is normally covered by the cap 29.

Upon the downward movement or cylinder A and cylinder 4, such as iscaused when the vehicle body is being loaded, or which also occurs byjolts when traveling and encountering the irregularities of roadwaysurfaces, the air in chamber 3 on being compressed above the inelasticoil will support or cushion the load of the vehicle body.

Separation of the cylinders which takes place when the body reboundscauses the cylinder 7 to move down in the direction of arrow a. Thisproduces a tendency to create a vacuum in the compartments 11 and 12,this being due to the difference in diameter of the chambers. 11 and 12as previouslydescribed. The production of vacuum when the parts areseparated checks any rebound and consequently eliminates the so-calledcatapult efiect which is so common inspring supported vehicles. The oilcollected in the compression chamber above piston 8. has a tendency togradually leak down by the piston and the cup-leather 19.. This oil is,however, replaced when compression takes place or when the} cylinder 7moves up with relation to piston 6. This coming together of the piston 6and cylinder 7 forces the oil through the opening 13 into thecompartment 11, which is of smaller diameter and capacity. The oil isconsequently forced through the radial openings 25, the central passage23 in the piston rod and by check valve 24 directly into the compressionchamber 3, where it is retained by the check valve which immediatelycloses when the cylinders separate.

Any air admitted to either-compartment 11 'or 12 will in'this manner-betrapped in the concave endof thepiston 6, and will, consequently, beforced back into the compression chamber ahead-cf the oil. A perfectlubrication of the several parts is-thus maintained, and an oil seal ontop of piston 8 is similarly maintained 'as each stroke of the cylinderforces a quantitygof oil back into chamber 3, where it accummulates ontop of the, piston; The seal maintained bv the oil admitted from thelubricating cup 17 prevents admission of air from'the exterior, andsimilarly prevents escape of air from the interior. The oil admittedalso thoroughly lubricates the contacting faces of the severalcylinders, consequently increasing the life and efiiciency of the.device as tions mutually check each other. The dis agreeable anddangerous shocks generally encountered on rough road surfaces are inthis manner entirely overcome, and comfortable and easy riding secured.Having thus described my invention. what I claim and desire to secure byLetters Patent is:

1. A pneumatic cushion device comprising a pair of cylinders, one beingof larger diameter than the other, and the smaller cyl inder beingmountedtelescope wise within the larger cylmder, a valved piston withinthe smaller cylmder dividing-the cylindersv into a cushion chamber andan oil chamber.

a piston having a central opening formed therein secured onthe lower endof. the

smaller cylinder, and said piston dividing the oil chamber into twocompartments, one being larger in diameter than the other, andcommunicating with each-other through the central opening and a solidrod secured to the valved piston and extending through the centralopening and spaced apart therefrom 120 and connected to the lower end ofthe larger cylmder. i

-2. A pneumatic, cushion device com-prise inga pair of cylinders, onebeing of larger diameter than the other and'the smaller cyl- 1 25indefbeing mounted telescope wise within the larger cyl1nder, a yalvedpiston within the smallercylinder dividing the cylinders.

into a cushion chamber and an oil chamher, a p ston secured on the lowerend of 130 The combination of the steel thesmaller cylinder and dividingthe oil said compartments, meansconnecting' the valved piston-with thelarger cylinder, a

head member forming a closure for the upper end or" the smallercylinder, a third cylinder carried by said head and inclosing thesmallerand larger cylinders and means for admitting oil to the spaceformed between.

inder being mounted telescope wise within the larger cylinder, a valvedpiston within the smaller cylinder dividing the cylinders intoa cushionchamber and an oil chamber,- a piston secured on'the, lower end of thesmaller cylinder and dividing the oil chamher into two compartments ofsmallerand larger diameters, an oil seal between said compartments,means connecting the valved piston with the larger cylinder, a headmember forming a closure for the upper end ofthe smaller cylinder, athird cylinder carried' by said head and inclosing the smaller andlarger cylinders, means for admitting oil to the space formed betweenthe third cylinder and the smaller cylinder, I and an "elf-set formed inthe upper end of the larger cylinder to receive the oil and to form aseal between the larger and smaller cylinders.

fl. A pneumatic cushion device comprising 'a pair of cylinders, onebeing of larger diameter than the other and the smaller cylinder beingmounted telescope wise within the larger cylinder, a-valved pistonwithin the smaller cvli'nder dividing the cylinders into a cushionchamber and an oil chamber, a piston secured on the lower 'end of thesmaller cylinder and dividing the oil chamber into two compartments ofsmaller and larger diameters, an oil seal between said compartments, :1.rod connecting the valved piston with the larger cylinder, said valvedpiston having a concave lower end, a central bore extending therethroughand entering the upper end of said rod, ports in said-rod forming acommunication between the concavity and the bore, and check valve forclosing the upper end of said bore.

5. A pneumatic cushioh device com-prising a pair of cylinders, one beingof larger diameter than the other and the smaller-cylinder being mountedtelescope wise within the larger cylinder, said smaller cylinder beingalso tapered. on the exterior surface to produce a smaller diameteratthe lower end, a valved piston within the smaller cylinder dividing thecylinders into a cushion chamber and an oil chamber, a piston having acentral opening formed therein secured on the lower end of the smallercylinder, said piston dividing the oil chamber into two compartments,one being larger in diameter than the other, and communicating with eachother through the central opening, a rod secured to the valved pistonand extending through the central opening and a socket connectionbetween the rod and the lower end of thevlarger cylinder.

. 6. A pneumatic cushion device comprising a pair of cylinders, onebeing of larger diameter than the other, and the smaller cylinder beingmounted telescope wise within the larger cylinder, a valved pistonwithin the smaller cylinder dividing the cylinders into a cushionchamber and an oil chamber, said'piston having-a concave bottom, apiston having a central'opening formed therein secured on the lowerendof the smaller cvlinder, said piston dividing the oil chamher into twocompartments, one being larger in diameter than the other, andcommunicating with each other through the central opening. arod securedto the valved piston, said rod having a passage formed thereincommunicating at one end with the valve and at the other end with theconcave bottom, and a socket connection between the rod and the lowerend of the larger piston, 7. pneumatic cushion device, comprischamberfor air and a lower chamber for,

oil, a plunger on the end of the upper cylinder operating within saidlower chamber and dividing the same into two inter-communicatingcompartments of differential diameters, packedsliding joints for thepiston and plunger, a valved communication between the two chambers, ajacket surrounding said cylinders and forming an' oil pocket overlyingthe joint therebetween, and an external source of oil supply for saidpocket, said differential diameter compart ments operating uponcompression of the cylinders to force oil from the lower chamber intothe upper chamber to maintain a seal for said packed joint, and on theextension of said cylinders creating a suction between the walls thereofwhichtends to draw oil into the lower chamber from said pocket. 8. Apneumaticcushion device, comprising in combination a pair of telescopingcylinders having their walls spaced slightly apart, a piston carried 'byone of said cylinders and slidable within the other forming between saidcylinders an upper chamber for air and a lower chamber-for oil, aplunger on the end of the upper cylinder operating within said lowerchamber and dividing the same into two inter-communicating compartmentsof differential diameters, packed sliding ointstor the piston and 111gin combination a pair of telescoping cylinders, a plston carried by oneof said plunger, said packed joints including an upturned, outwardlyexpanded cup-leather from the lower chamber into the upper her from saidpocket.

chamber to maintain a seal for said packed joint, and onthe extension ofsaid cylinders creatinga suction between the walls thereof which tendsto draw oil into the lower cham- 9; An air spring comprising a pair ofcylinders mounted one within the other and spaced from each other toform an intermediate annular chamber, a head member to which saidcylinders are secured, a third cylinder telescoping into the annularchamher, a piston on the innermost of the first named cylinders slidablymounted within the third cylinder, a piston rod secured tothe thirdcylinder by a socket connection, and a piston secured on the oppositeend of said rod slidably mounted within the innermost of the first namedcylinders.

10. An air spring comprising a pair of cylinders mounted one within theother and spaced from each other to form an intermediate annularchamber, a head member to which said cylinders are secured, a thirdcylinder telescoping into the annular chamber, a piston on the innermostof the first named cylinders slidably mounted within the third cylinder,the third cylinder by a socket connection. a piston secured on theopposite end of said rod slidably mounted within the innermost of thefirst named cylinders; a cup leather mounted on each piston, a taperedspreading head slidably mounted on each piston adapted-to enter the cupleather, and a spring bea piston rod secured tohind each spreading headadapted to force said head into the cup leather.

11. An air spring comprising a head member, an inner and an outercylinder spaced from each other, secured to the head member, and formingan annular chamber between said cylinders, a lower cylinder adapted totelescope into said annular chamher, a head member on the lowercylinder, a piston slidably mounted in the inner cylinder, a piston rodon said piston, a socket joint connecting the piston rod with the headon the lower cylinder, and a piston, secured on the lower end of theinner cylinder slidably mounted in the lower cylinder.

12. An air spring comprising a head member, an inner and an outercylinder spaced from each other, secured to the head member, and formingan annular chamber between said cylinders, a lower cylinder adapted totelescope into said annular chamher, a head member on the lowercylinder, a piston slidably mounted in the inner cylinder, a piston rodon said piston, a socket joint connecting the piston rod with the headon the lower cylinder, and a piston, secured on the lower end of theinner cylinder slidably mounted in the lower cylinder, said last-namedpiston having'a central passage through which the first named piston rodpasses, said passage forming a communication between two chambers formedbelow and above said piston, a third chamber formed between the head andthe first named piston, means for automatically maintaining an oil sealabove said firstnamed piston, and means for supplying oil to the annularchamber.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

Lucian a. Gauss Witnesses JOHN H. HERRING, A, B. 'BUN'r.

